Global Patent Index - EP 1494014 A1

EP 1494014 A1 20050105 - System with a ferro-electric liquid crystal for two-fold optical inspection of containers

Title (en)

System with a ferro-electric liquid crystal for two-fold optical inspection of containers

Title (de)

Gerät mit einem ferro-elektrischen Flüssigkristall zur zweifachen optischen Inspektion von Behältern

Title (fr)

Système comprenant un cristal liquide ferro-électrique pour l'inspection optique double des conteneurs

Publication

EP 1494014 A1 20050105 (EN)

Application

EP 04253478 A 20040610

Priority

US 61041703 A 20030630

Abstract (en)

An inspection system is provided which carries out two inspections with a single camera (26). In one inspection, polarized light illuminates the side wall of a bottle, passes through a pair of electrode surfaces (18, 22) on either side of a ferroelectric crystal device (20) which do not change the polarity, and passes through a polarizer (24) to image on the camera. In a second inspection the polarized light is rotated 90° by the same structure so that only light rotated as a result of stress in the bottle passes through the polarizer and images on the camera as a defect.

IPC 1-7

G01N 21/90; G01N 21/21; G02F 1/13; G02F 1/141

IPC 8 full level

G01N 21/21 (2006.01); G01N 21/90 (2006.01); G02F 1/13 (2006.01); G02F 1/141 (2006.01); H04N 7/18 (2006.01)

CPC (source: EP US)

G01N 21/21 (2013.01 - EP US); G01N 21/90 (2013.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

DE FR GB IT

DOCDB simple family (publication)

EP 1494014 A1 20050105; EP 1494014 B1 20071114; DE 602004010000 D1 20071227; DE 602004010000 T2 20080403; JP 2005024547 A 20050127; JP 4612345 B2 20110112; US 2004263618 A1 20041230; US 6989857 B2 20060124

DOCDB simple family (application)

EP 04253478 A 20040610; DE 602004010000 T 20040610; JP 2004162740 A 20040601; US 61041703 A 20030630